File manager

import typing as t

if t.TYPE_CHECKING:
    from .runtime import Undefined


class TemplateError(Exception):
    """Baseclass for all template errors."""

    def __init__(self, message: t.Optional[str] = None) -> None:
        super().__init__(message)

    @property
    def message(self) -> t.Optional[str]:
        return self.args[0] if self.args else None


class TemplateNotFound(IOError, LookupError, TemplateError):
    """Raised if a template does not exist.

    .. versionchanged:: 2.11
        If the given name is :class:`Undefined` and no message was
        provided, an :exc:`UndefinedError` is raised.
    """

    # Silence the Python warning about message being deprecated since
    # it's not valid here.
    message: t.Optional[str] = None

    def __init__(
        self,
        name: t.Optional[t.Union[str, "Undefined"]],
        message: t.Optional[str] = None,
    ) -> None:
        IOError.__init__(self, name)

        if message is None:
            from .runtime import Undefined

            if isinstance(name, Undefined):
                name._fail_with_undefined_error()

            message = name

        self.message = message
        self.name = name
        self.templates = [name]

    def __str__(self) -> str:
        return str(self.message)


class TemplatesNotFound(TemplateNotFound):
    """Like :class:`TemplateNotFound` but raised if multiple templates
    are selected.  This is a subclass of :class:`TemplateNotFound`
    exception, so just catching the base exception will catch both.

    .. versionchanged:: 2.11
        If a name in the list of names is :class:`Undefined`, a message
        about it being undefined is shown rather than the empty string.

    .. versionadded:: 2.2
    """

    def __init__(
        self,
        names: t.Sequence[t.Union[str, "Undefined"]] = (),
        message: t.Optional[str] = None,
    ) -> None:
        if message is None:
            from .runtime import Undefined

            parts = []

            for name in names:
                if isinstance(name, Undefined):
                    parts.append(name._undefined_message)
                else:
                    parts.append(name)

            parts_str = ", ".join(map(str, parts))
            message = f"none of the templates given were found: {parts_str}"

        super().__init__(names[-1] if names else None, message)
        self.templates = list(names)


class TemplateSyntaxError(TemplateError):
    """Raised to tell the user that there is a problem with the template."""

    def __init__(
        self,
        message: str,
        lineno: int,
        name: t.Optional[str] = None,
        filename: t.Optional[str] = None,
    ) -> None:
        super().__init__(message)
        self.lineno = lineno
        self.name = name
        self.filename = filename
        self.source: t.Optional[str] = None

        # this is set to True if the debug.translate_syntax_error
        # function translated the syntax error into a new traceback
        self.translated = False

    def __str__(self) -> str:
        # for translated errors we only return the message
        if self.translated:
            return t.cast(str, self.message)

        # otherwise attach some stuff
        location = f"line {self.lineno}"
        name = self.filename or self.name
        if name:
            location = f'File "{name}", {location}'
        lines = [t.cast(str, self.message), "  " + location]

        # if the source is set, add the line to the output
        if self.source is not None:
            try:
                line = self.source.splitlines()[self.lineno - 1]
            except IndexError:
                pass
            else:
                lines.append("    " + line.strip())

        return "\n".join(lines)

    def __reduce__(self):  # type: ignore
        # https://bugs.python.org/issue1692335 Exceptions that take
        # multiple required arguments have problems with pickling.
        # Without this, raises TypeError: __init__() missing 1 required
        # positional argument: 'lineno'
        return self.__class__, (self.message, self.lineno, self.name, self.filename)


class TemplateAssertionError(TemplateSyntaxError):
    """Like a template syntax error, but covers cases where something in the
    template caused an error at compile time that wasn't necessarily caused
    by a syntax error.  However it's a direct subclass of
    :exc:`TemplateSyntaxError` and has the same attributes.
    """


class TemplateRuntimeError(TemplateError):
    """A generic runtime error in the template engine.  Under some situations
    Jinja may raise this exception.
    """


class UndefinedError(TemplateRuntimeError):
    """Raised if a template tries to operate on :class:`Undefined`."""


class SecurityError(TemplateRuntimeError):
    """Raised if a template tries to do something insecure if the
    sandbox is enabled.
    """


class FilterArgumentError(TemplateRuntimeError):
    """This error is raised if a filter was called with inappropriate
    arguments
    """